1. Technical Field
The present invention relates to a screen on which an image is displayed, and particularly to a screen on which an image according to projected light incident in an oblique direction from a projector or any other image projection apparatus is displayed.
2. Related Art
There are screens that are known to display an image projected from a projector or any other image projection apparatus. One of the screens of this type can reflect light incident from the projector toward a viewing position in front of the screen even when the distance between the projector and the screen is small (see JP-A-2010-96883, for example).
The screen described in JP-A-2010-96883 has a plurality of concave lens elements arranged over a light incident surface, and a light reflection layer is formed on the surface of each of the lens elements. Part of the light incident on the light reflection layer is reflected toward the viewing position and visually recognized as an image in the viewing position.
When projected light is incident in an oblique direction on a screen, such as the one described in JP-A-2010-96883, and a normal to the incident surface of the screen and the optical path of the projected light incident on the incident surface form a relatively small angle, a light flux incident on each of the lens elements has a wide width. When a light flux has a wide width, light of a small degree of concentration is incident on a wide area of each of the lens elements described above. In this case, since only a small amount of light is incident on an effective reflection region that is part of the light reflection layer described above and effectively reflects light incident thereon toward the viewing position, a displayed image is disadvantageously not very bright.